Active ingredients: Benzocaine

Pharmacodynamic properties

ATC code: R02AD01

Benzocaine is a local anaesthetic of the ester type. The mode of action is a reversible inhibition of the flux of sodium and potassium ions through the axonal membranes of peripheral pain receptors. As a consequence, the depolarisation and propagation of nerve impulses are inhibited.

The onset of action of benzocaine on mucous membranes is rapid due to the spray delivery of the anaesthetic direct to the site of action, rapid absorption, and the surface analgesic effect. The local anaesthesia induced by benzocaine is temporary but Ultra Chloraseptic spray has not been tested for duration of action.

Pharmacokinetic properties

Benzocaine is absorbed into the mucosal membranes. After systemic absorption, which is negligible, the drug is thought to be metabolised to ethanol and aminobenzoic acid by plasma esterases. Aminobenzoic acid is excreted unchanged or conjugated with glycerine to amoniohippuric acid in the liver, the metabolites and unchanged benzocaine are excreted in the urine.

Preclinical safety data

No animal data are available on Ultra Chloraseptic spray. Non-clinical studies on benzocaine showed local irritation and sensation, and methaemoglobinaemia at high doses in some species.